问题 问答题 简答题

压缩气体和液化气体有何性质?是如何认定和分项的?

答案

参考答案:

压缩气体和液化气体的特性有:

(1)受热膨胀性;

(2)气体的易爆性及毒害性。

符合下列条件之一的气体,均属于压缩气体和液化气体;

(1)在50°C时其蒸气压力大于300KPa;

(2)在20°C及101.3KPa的标准压力下为气态的物质。

压缩气体和液化气体按其性质分为三项:

(1)易燃气体;

(2)不燃气体;

(3)有毒气体。

阅读理解

Different weather makes people feel different. It influences (影响) health, intelligence (智力) and feelings.

In August, it is very hot and wet in the southern part of the United States. People there have heart trouble and other kinds of health problems during this month. In the Northeast and the Middle West, it is very hot at some times and very cold at other times. People in these states have more heart trouble after the weather changes in February or March.

The weather can also influence intelligence. For example, in a 1983 report by scientists, IQ (智商) of a group students were very high when a very strong wind came, but after the strong wind, their IQ was 10% below. The wind can help people have more intelligence. Very hot weather, on the other hand (另一方面), can make it lower. Students in many schools of the United States often get worse on exams in the hot months of the year (July and August).

Weather also has a strong influence on people’s feelings. Winter may be a bad time for thin people. They usually feel cold during these months. They might feel unhappy during cold weather. But fat people may have a hard time in hot summer. At about 18C, people become stronger.

Low air pressure (气压) may make people forgetful. People leave more bags on buses and in shops on low-pressure days. There is a “good weather” for work and health. People feel best at a temperature of about 18 centigrade (摄氏度).

Are you feeling sad, tired, forgetful, or unhappy today? It may be the weather’s problem.

小题1:People may have more intelligence when _____ comes.

A.a rain

B.very hot weather

C.a strong wind

D.low air pressure小题2:Low air pressure may make people _______.

A.forgetful

B.sad

C.angry

D.tired小题3:In “good weather” of 18 centigrade, _______.

A.people are very forgetful

B.people can’t do their work well

C.thin people feel cold

D.people are in better health小题4:The writer wants to tell us that _______.

A.hot and cold weather influences all people in the same way

B.weather influences people’s lives

C.IQ never changes during weather changes

D.There is a good kind of weather for people’s work and health

判断题